1. Field of the Invention
This invention is related to a method for epoxidizing an unsaturated polymer, and more particularly, related to a method for epoxidizing a polymer having a conjugated diene group by using a homogeneous catalyst.
2. Description of the Prior Art
Polymers with a conjugated diene group or polymers with a vinyl aromatic group and a conjugated diene group, such as butadiene polymers, styrene-butadiene or styrene-isoprene polymers, have been successfully commercialized and applied to elasticity materials, adhesives, polymer modifiers, etc. because of excellent elasticity. To expand the application of those polymers, many efforts have been made to epoxidizing of conjugated diene group to enhance the polarity and then get the compatibility with much polar polymer and metal.
The conventional technology of epoxidization of conjugated diene group is mainly prepared by epoxidizing the unsaturated double bond of polymer with acetic ester as catalyst and peroxide as oxidant, as illustrated in U.S. Pat. No. 5,840,809. However, different challenges still exist for each application. For example, in the conventional technology, the epoxidized polymer needs to proceed many cycles of extraction and standing still to get purified product. The procedure is very complicated and time consuming. Therefore, only continuous research for various novel epoxidizing polymerizations can meet all the criteria of different applications.